Cross-Layer Analysis of Cognitive Radio Relay Networks under Quality of Service Constraints

In this paper, we investigate the performance gains of cognitive radio relay networks under delay quality of service (QoS) limitations at the secondary users, and spectrum-sharing restrictions imposed by the primary users of the channel. In particular, we assume that the primary user allows secondary users to gain access to its allocated spectrum band as long as a certain threshold on its corresponding outage probability is satisfied. Using this constraint, we find the maximum limit on the interference-power inflicted on the primary receiver that should not be exceeded by the transmission of the secondary users. In addition, we assume that the secondary transmitter benefits from an intermediate node, chosen from K terminals, to relay its signal to the destination. Considering that the transmission of the secondary user is subject to satisfying a statistical delay QoS constraint, we obtain the maximum arrival-rate supported by the secondary user's relaying link. In this respect, we derive closed-form expressions for the effective capacity of the channel in Rayleigh block-fading environment. Numerical simulations are provided to endorse our theoretical results.

[1]  Jia Tang,et al.  Quality-of-Service Driven Power and Rate Adaptation over Wireless Links , 2007, IEEE Transactions on Wireless Communications.

[2]  Abbas El Gamal,et al.  Capacity theorems for the relay channel , 1979, IEEE Trans. Inf. Theory.

[3]  Joseph Mitola,et al.  Cognitive radio: making software radios more personal , 1999, IEEE Wirel. Commun..

[4]  Anders Høst-Madsen,et al.  Capacity bounds and power allocation for wireless relay channels , 2005, IEEE Transactions on Information Theory.

[5]  Michael Gastpar.  On Capacity Under Received-Signal Constraints , 2004 .

[6]  Jon M. Peha,et al.  Approaches to spectrum sharing , 2005, IEEE Communications Magazine.

[7]  Ian F. Akyildiz,et al.  NeXt generation/dynamic spectrum access/cognitive radio wireless networks: A survey , 2006, Comput. Networks.

[8]  Dapeng Wu,et al.  Effective capacity: a wireless link model for support of quality of service , 2003, IEEE Trans. Wirel. Commun..

[9]  Pramod Viswanath,et al.  Cognitive Radio: An Information-Theoretic Perspective , 2009, IEEE Transactions on Information Theory.

[10]  Pravin Varaiya,et al.  Capacity of fading channels with channel side information , 1997, IEEE Trans. Inf. Theory.

[11]  Cheng-Shang Chang,et al.  Stability, queue length, and delay of deterministic and stochastic queueing networks , 1994, IEEE Trans. Autom. Control..

[12]  Leila Musavian,et al.  Quality-of-Service Based Power Allocation in Spectrum-Sharing Channels , 2008, IEEE GLOBECOM 2008 - 2008 IEEE Global Telecommunications Conference.

[13]  Sonia Aïssa,et al.  Capacity and power allocation for spectrum-sharing communications in fading channels , 2009, IEEE Transactions on Wireless Communications.

[14]  Friedrich Jondral,et al.  Spectrum pooling: an innovative strategy for the enhancement of spectrum efficiency , 2004, IEEE Communications Magazine.

[15]  Vahid Asghari,et al.  Resource Sharing in Cognitive Radio Systems: Outage Capacity and Power Allocation under Soft Sensing , 2008, IEEE GLOBECOM 2008 - 2008 IEEE Global Telecommunications Conference.